Senior Fullstack Engineer, React/Kotlin

Jobtailor; Deutschland; Remote; EUR 70.000 - 110.000; Vollzeit

Zusammenfassung

Jobtailor in Germany seeks an experienced software engineer to design, build, and scale customer-facing applications using React and TypeScript, while developing backend services in Kotlin.

You will own features end-to-end, collaborate with product and design teams, mentor peers, and help improve engineering practices, testing, and deployment processes across e-commerce and fintech domains.

Qualifikationen

• 5–8 years of professional software engineering experience with production-grade customer-facing products.
• Advanced experience with React and TypeScript for modern web apps.
• Strong frontend performance, accessibility, and component architecture knowledge.
• Backend design and Kotlin development experience, including APIs and data models.
• Experience with service-oriented or distributed systems and scalable architectures.
• Knowledge of React Native and delivering consistent mobile experiences.
• Experience with automated testing, observability, and progressive deployments.
• Experience supporting production systems and on-call rotations.
• Ability to own initiatives across the full software lifecycle and collaborate cross-functionally.
• Experience with Python and experimentation / A/B testing platforms.

Aufgaben

• Design, build, and maintain scalable customer-facing applications using React and TypeScript.
• Develop and evolve backend services and APIs using Kotlin.
• Contribute to React Native mobile experiences when needed.
• Own features and technical initiatives from problem definition through testing and production support.
• Collaborate with Product, Design, Analytics, and Engineering teams across domains.
• Design systems with scalability, availability, performance, maintainability, and cost efficiency in mind.
• Implement automated testing, observability, and safe deployment strategies.
• Troubleshoot production issues and participate in on-call responsibilities.
• Communicate technical decisions and delivery progress to stakeholders.
• Mentor engineers and drive continuous improvement of engineering practices.

Kenntnisse

React

TypeScript

Kotlin

API Design

Automated Testing

Performance Monitoring

React Native

Python

Service-Oriented Architecture

E-Commerce App Development

Tools

A/B Testing Platforms

Observability Tools

Production Debugging Tools

Jobbeschreibung

• Design, build, and maintain scalable customer-facing applications using React and TypeScript
• Develop and evolve reliable backend services and APIs using Kotlin
• Contribute to React Native mobile experiences when needed
• Own features and technical initiatives from problem definition and design through development, testing, deployment, and production support
• Build experiences that improve merchant and offer discovery, purchasing decisions, and checkout journeys
• Translate complex or ambiguous product requirements into clear technical solutions and incremental delivery plans
• Collaborate with Product, Design, Analytics, and Engineering teams across multiple technical domains
• Design systems with scalability, availability, performance, maintainability, and cost efficiency in mind
• Implement automated testing, observability, performance monitoring, and safe deployment strategies
• Troubleshoot production issues and participate in on-call responsibilities
• Communicate technical decisions, dependencies, risks, tradeoffs, and delivery progress clearly with technical and non-technical stakeholders
• Participate in design and code reviews, technical documentation, mentoring, and continuous improvement of engineering practices

Requirements

• 5–8 years of professional software engineering experience, including experience building and operating customer-facing products in production
• Advanced experience developing modern web applications with React and TypeScript
• Strong understanding of frontend component architecture, state management, automated testing, performance, and accessibility
• Professional experience designing and developing backend services using Kotlin
• Experience designing APIs, data models, asynchronous workflows, and service-to-service integrations
• Working knowledge of React Native and patterns for delivering consistent mobile experiences
• Experience designing service-oriented or distributed systems with scalability, availability, low latency, maintainability, and cost efficiency in mind
• Experience with automated testing, observability, production debugging, and progressive deployment strategies
• Experience supporting and operating production systems, including participation in on-call rotations
• Demonstrated ability to take ownership of initiatives across the full software development lifecycle
• Strong communication skills and experience collaborating with distributed, cross-functional teams
• Ability to work effectively with US-based clients and stakeholders
• Strong product mindset with the ability to connect technical decisions to customer experience and measurable business outcomes
• Ability to navigate ambiguity, evaluate technical tradeoffs, and turn broad requirements into practical solutions
• Experience with Python
• Experience with experimentation or A/B testing platforms
• Experience building high-traffic e-commerce, marketplace, shopping, or fintech applications
• Experience working on systems involving offers, promotions, payments, or transaction workflows
• Experience mentoring engineers and helping improve engineering standards across a team

Core Competencies

Demonstrates expertise in building scalable customer-facing applications using React and TypeScript, while also developing reliable backend services with Kotlin. Strong ability to translate complex product requirements into technical solutions and effectively communicate with cross-functional teams.

Highest-signal resume keywords

• React Application Development
• TypeScript Proficiency
• Kotlin Backend Development
• Automated Testing Implementation
• Cross-Functional Collaboration

ATS Optimization Keywords

Hard Skills

• React
• TypeScript
• Kotlin
• API Design
• Automated Testing
• Performance Monitoring
• React Native
• Python
• Service-Oriented Architecture
• E-Commerce Application Development

Soft Skills

• Strong Communication Skills
• Problem-Solving
• Mentoring

Industry Keywords

• Customer-Facing Products
• Scalability
• Availability
• Low Latency
• Transaction Workflows

Tools & Technologies

• A/B Testing Platforms
• Observability Tools
• Production Debugging Tools